The invention relates to a drive and folding mechanism for an apparatus for laying an in particular unfolded fibrous material web, in particular a paper web or a corrugated paper web like a corrugated cardboard web in a Leporello folding.
A corrugated cardboard web is often used for packaging purposes in that, for example, separated layers of corrugated cardboard are put for cushioning transported goods adjacent to each other. A sheet of corrugated cardboard can present a contour on one side or on two sides. For a corrugated cardboard web with a contour on one side only, one side is formed by a layer of corrugated paper onto which a smooth layer of paper is glued for forming the other side. It shall be understood that the corrugated cardboard web can be formed by several flat and corrugated layers of paper put upon each other in order to increase the buffer characteristics.
In order to optimise the packaging process it is common to draw the packaging material from a packaging material source that is present either as a reel or as a Leporello-folded stack. The Leporello-folded stack is often preferred due to its rectangular outer shape and the resulting ease of storage and simple webs. The pulling off or unfolding from a Leporello-folded stack is relatively simple because no strongly dimensioned rotary bearings for a reel of corrugated cardboard are necessary. However, corrugated cardboard webs are usually provided by the paper makers in reels so that for creating a Leporello-folded stack the corrugated cardboard web first needs to be unreeled from the endless rollers and appropriately Leporello-folded.
An apparatus for laying an in particular unfolded, endless fibrous material web in a Leporello fold, which apparatus comprises a drive mechanism is known from DE 196 44 383 C1. The known Leporello folding apparatus has a platform onto which a fibrous material stack can be put by means of a stack forming mechanism. The fibrous material web is guided via several rollers from a fibrous material web source to a drive mechanism that is formed by two drive belts arranged in parallel to each other. The drive belts are arranged vertical with respect to the platform and guide the fibrous material web vertically downwards. In order to achieve the Leporello-type zigzag folding, the vertically orientated drive belts are translationally displaced back and forth in horizontal direction.
A drive mechanism for a Leporello folding apparatus is also known from DE 35 00 766 A1, in which a driving roller arranged ahead of a pair of pendulum rods pulls a web of material off a material web source and feeds it to the pair of pendulum rods which is designed to form a Leporello fold by means of a back and forth pivoting motion.
DE 19 64 858 discloses a drive mechanism for a Leporello folding apparatus in which a pulling roller pulls off the material web stationary fixed at a holder. A pivot arm is driven via a multilink chain, and the pulling roller feeds the material web towards the end of the pivot arm.
All the above named, known drive mechanisms for a Leporello folding apparatus have the disadvantage of requiring a large amount of space in order to realise the drive mechanism by means of drive belts or a combination of a driving roller and a pivoting mechanism. Furthermore, for the known drive mechanisms a large requirement for construction material as well as a large wear of those materials is to lamented and a large number of components is required.